Cannibalism is a theme that comes up many times during the Iliad. Mostly its subversion because eating another human being would put oneself above other humans aka a god. Only one human character threatens cannibalism and that is Achilles when Hector asks for his body to be given back to his family and he is pretty upset so you know, when you’re upset OF COURSE you threaten cannibalism, right?
Other than that the fear of being eaten after death is present everywhere in the story especially with the theme of dead bodies being threatened to be thrown to the birds and dogs for food.
So while I am sure the rear is not the prime target of the fear of being eaten, your AU is a very general fear of the mortal characters in the epic.